The massaging of the gums of the mouth is extremely important to persons of every age. Vigorous but controlled massaging stimulates circulation of the blood within the gums, and maintains them in a strong, healthy state. Massaging of the gums, together with efficient cleaning of the exposed surfaces of the teeth, helps among other things to avoid the serious condition known as pyorrhea, which is an inflammation of the sockets of the teeth usually leading to loosening of the teeth.
If the gums of the mouth are not maintained in a healthy condition, it may become necessary to cut the gums back surgically. In extreme cases, it may become necessary to extract the teeth, if the gums become so deteriorated through lack of proper attention as to no longer support the teeth properly.
A variety of mechanical gum massaging devices has been known for many years. The type of movement of the stimulating or massaging element in these devices falls in several different categories. Each of these categories has disadvantages, and fails to achieve the most effective massaging action of the gums.
U.S. Pat. No. 955,339 issued to Lumsden on Apr. 19, 1910 discloses a mechanical massaging device which can be used for massaging the gums of the mouth if appropriate stimulating or massaging elements are employed, even though there is no reference in the patent to this specific use. In this device, the force-applying element is caused to follow a circular path in a plane perpendicular to the surface being treated. Because of this type of movement, if the device is held stationary the stimulating element would be spaced from the gum surface under treatment most of the time, and in contact with that surface only where the circular path is tangent to the gum surface. The result would be, in other words, only intermittent contact of very brief duration between the massaging element and the gum surface being treated. In fact, the contact would be so brief, and the distance travelled by the stimulator element away from and towards the gum surface would be so great, that the resulting contact would approach in effect a series of "trip hammer" blows that would be likely actually to damage the gums instead of stimulating them. French patent No. 1,216,838 published Apr. 27, 1960 discloses a mechanical toothbrush that has the same circular action as the Lumsden device -- as well as the same disadvantages as that device -- if handle 8 in FIG. 1 and handle 24 in FIG. 3 are circular in cross section.
The patent to Groff U.S. Pat. No. 1,833,967 issued Dec. 1, 1931 discloses a mechanical toothbrush in which there is continuous contact between the bristles of the brush and the teeth, as the brush rotates, for that portion of the circumference of the assemblage of bristles that is in contact with the teeth. If the bristles are soft, little massaging effect will result. On the other hand, if the bristles are relatively stiff and this toothbrush is held stationary in one location on the gums for any period of time, the continuous contact of the bristles and the gums could produce an abrasive effect in that small area of the gums. Later patents to Barckley U.S. Pat. No. 3,033,197 issued May 8, 1962 and to Gonzalez U.S. Pat. No. 3,034,376 issued May 15, 1962 disclose mechanically operated brushes that provide a similar type of movement. French patent No. 1,133,470 published Mar. 27, 1957 has a similar rotary brushing action. All these patents have the same disadvantages as the Groff device.
Other patents disclose mechanical devices adapted to brushing the teeth and/or massaging the gums in which the force-applying element maintains continuous and uniform contact with the surface being treated, oscillating back and forth through a relatively small arc. This type of movement provides continuous contact with, and uniform application of force upon, whatever small portion of the surface being treated is included within the travel of the oscillating element. It thus provides no period during which that small portion of the surface is free of massaging or brushing force or even subjected to forces of periodically varying magnitude. In addition, since the direction of application of force is diametrically reversed every half cycle of the oscillatory movement while the magnitude of the force remains the same, these devices do not produce a massaging action having a dominant component in any consistent direction. As a consequence, these devices have a low resultant massaging force, and could actually produce abrasion instead of stimulation of the gums. The patents to Blair U.S. Pat. No. 2,135,933 issued Nov. 8, 1938, Bobbroff U.S. Pat. No. 2,282,700 issued May 12, 1942, Demanuele U.S. Pat. No. 2,977,614 issued Apr. 4, 1961, and FIGS. 1-6 of Huebner patent U.S. Pat. 3,183,538 issued May 18, 1965 provide examples of such devices.
The patents to Lasater U.S. Pat. No. 2,206,726 issued July 2, 1940 and Buck U.S. Pat. No. 2,319,205 issued May 18, 1943 disclose mechanical toothbrushes which are referred to as providing both a tooth cleaning function and a gum massaging function, but which actually operate to produce an even more drastic "trip hammer" effect upon the surface being treated than do the Lumsden patent and French patent No. 1,216,838 discussed above. In these patents, the stimulator element is caused to vibrate back and forth through an oscillatory path that is generally elliptical in shape, with the major axis of the ellipse being oriented in the direction of application of massaging force. This causes the stimulator element to strike the teeth and gums with a continuous series of quite sharp, intermittent blows. Use of this type of device necessarily exposes the user to the potentially damaging effect of any series of hammer blows upon the gums of the mouth.
Still another type of tooth cleaning and gum massaging device is disclosed in the patent to Gregoire U.S. Pat. No. 2,808,602 issued Oct. 8, 1957, the patent to Miller U.S. Pat. No. 3,012,263 issued Dec. 12, 1961, British patent No. 899,618 issued to Peyron with a publication date of June 27, 1962, and FIGS. 5-12 and 17-21 of the above mentioned patent to Huebner U.S. Pat. No. 3,183,538. These devices provide continuous rotary contact of a brushing, massaging or drilling element with the surface being treated. Even when an element otherwise suitable for massage is employed, this form of contact fails to produce the most desirable massaging effect, and could in fact have a harmful abrasive effect on the gums.